Intangible Assets, Net (Details) - JPY (¥) ¥ in Thousands	6 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Intangible Assets, Net [Abstract]
Amortization of intangible assets	¥ 8,782	¥ 4,937

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets.

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